Software That Can’t Fail

I started working at Microsoft when I was 18 years old. It paid better than the landscaping job I was enjoying at the time. I didn’t know much about writing code, but I was fairly proficient with computers and wanted to learn more. There seemed to be a real opportunity to help make some great software. After about 1 year on the job, I read this article titled, “They Write the Right Stuff” It captured my idealistic young mind! The idea that you could write software in such a way as to be almost perfect seemed both exciting and achievable!

After more than two decades of working with software, I have become painfully aware of how truly difficult it is to build software that is defect free, let alone on time and under budget. There are so many strong forces pulling away from this lofty ideal.

Still, there are some bits of code, even some large bits of code, that simply must not fail. The space shuttle control system is the example cited in the article. But there are other mission critical systems have to “just work.” One of these foundational types of software that must not fail are file systems. Everything depends upon them. Their role is unheralded, but so critical.

Last March, almost exactly 1 year ago, Apple announced a new file system, dubbed the Apple File System, or APFS for short. I was excited for the future improvements, but saw this as a multi-year roll out at best. You don’t just swap out the foundation for a skyscraper on a whim. These things take time… unless you are Apple.

Last Monday, just 3 days ago, Apple released an update to iOS (specifically iOS 10.3) to millions of iPhones and iPads worldwide and with this update the existing file system is converted to APFS. The risks involved here are staggering in my mind, yet Apple has seemed to pull it off. I’m still holding my breath, but it’s worth taking some time to contemplate the achievement here. It doesn’t happen very often, but it does happen, and it’s as beautiful as the Space Shuttle safely lumbering towards it’s orbital rendezvous in the vacuum of space.

Maybe Apple is ready to write the software that drives our cars, or maybe this is just an anomaly all the more beautiful for it’s rarity.